1. Field of the Invention
The invention relates in general to a lens structure, and more particularly to a lens structure with multiple barrels.
2. Description of the Related Art
Along with the advance in technology, digital camera mechanism has been widely used in various digital products such as digital camera, digital video recorder, mobile phone, personal digital assistant (PDA). The digital camera mechanism comprises a lens structure and an image sensor. The lens structure focuses an image on the image sensor, which then converts an optical image signal into an electrical signal.
Conventional lens structure comprises a number of barrels which move relatively to each other. A straight forward barrel of the barrels has a groove, which defines an optical zooming path. Through the groove, the straight forward barrel may move in a straight line to zoom in and/or zoom out.
Since the optical zooming path is defined by the groove of only one straight forward barrel, the length of the optical zooming path is limited. However, to increase the length of the optical zooming path, the thickness of the straight forward barrel needs to be increased, and the increase in thickness will increase the volume of the digital camera mechanism and reduce product competitiveness.